EP1058917B1 - Loading block computer programmes - Google Patents

Description

The invention relates to loading programs. data processing in a memory of a portable object and in particular in a memory of a smart card.

Chip cards are portable or portable objects consist, on the one hand, of a card body and, on the other hand, of a chip.

The chip includes an integrated circuit on the surface of a substrate silicon, said circuit defining in particular memory zones of the chip as well as a microcontroller part ensuring in particular the data management between the different memory areas.

This chip, reported in an electronic module or not, is integrated into the card body and communicates with the outside world by means of electrical contacts or an antenna. According to its mode of communication, the card is said to contact or contactless, being however understood that so-called combined cards are likely to communicate according to the two modes of communication with and without touching.

Conventionally, smart cards are used in applications in which they identify their carrier and allow, for example, said holder to obtain a right such as right of access to services or to carry out transactions.

Access to services sometimes requires that a program computer is loaded into a memory of the card (see EP-A-795444).

Nevertheless, these computer programs have sizes of larger and larger today reaching 8 kBytes and will reach 64 kBytes in the near future.

However, the operating rates of the micro-controller of the card as well as the memory write time do not allow instant loading of important programs.

For example, the loading time of a program 8 kBytes in a contactless card from a device transmitter is on the order of a minute, which is far too long for allow loading of the program in average time during which the card is in the useful electromagnetic field of said transmitting device, in particular if the fact is taken into account that this device must manage a plurality of cards as well as the possible collisions between said cards.

In practice, the loading is then interrupted and it is then necessary to wait until the time spent in the field of another transmitter device is long enough for the charging of the program is carried out in its entirety with success.

Also, in view of the above, a problem that arises proposes to solve the invention is to allow the loading of a program without loading time constraints influencing actually on loading said program successfully.

In view of this problem, the proposed solution of the invention has relates to a method for loading computer programs in a memory of a portable memory object having a contactless operating mode according to claim 1.

Advantageously, the method of the invention comprises in in addition to the following stages, according to which: - FLG means of the portable object indicates to an emitting device EMj the state in loading FLG = Y or not FLG = N of the portable object; and - prior to resumption of loading at the BLKi block, the state in whether or not the portable object is charged is checked.

The invention will be better understood on reading the description not restrictive which will follow.

The method of the invention applies to portable objects or portable with memory and, preferably, with smart cards whose format and characteristics are defined in the standards ISO 78-10 and 78-16 the content of which is incorporated herein stated by reference quote or applies, plus preferentially, to such cards however having a mode contactless operation optionally in addition to a conventional operation, with contacts said cards being characterized in particular in ISO 14443 standards.

Contactless smart cards have an integrated circuit in a silicon substrate, the assembly, circuit and substrate, constituting the chip, said chip being either integrated into an electronic module integrated into a card body, or integrated directly in said card body.

The integrated circuit defines different memories of the chip and in particular at least one volatile memory RAM and at least one non-volatile memory ROM, this non-volatile memory or one of the non-volatile memories being, if necessary, a memory electrically programmable and erasable EEPROM or memory Flash PROM type. In addition, the integrated circuit defines a unit central CPU or microcontroller, said central unit performing in in particular the management of data between the different memories, by via an address bus and a data bus, said bus management being clocked according to clock cycles.

The invention aims to load a computer program PRG in one of the card memories and in particular in a non-volatile memory of the EEPROM type of said card.

Such a PRG program is a dataset for example defining a set of instructions executable by the card. This is the case with application programs written in high level Java-like languages called applets. These are, in one example, programs allowing access to services such as, in the case of a bank card, a program allowing the card to perform applications of electronic purse. The size of PRG programs is more or less important. However, the invention shows great interest in the case of large programs, in particular of the order or greater than 2 kBytes, for example 8 kBytes, or even 64 kBytes whose total practical charging time is more than 5 seconds.

In the embodiment described in this presentation, the PRG program is loaded into the card's EEPROM memory, from one or more transmitting readers EM1, ..., EMj, ... EMp, p being a natural number greater than or equal to 1, each EMj transmitter device with a copy of the program or being likely to obtain such a copy from an associated server, under operator control.

For loading, the PRG program is divided according to the invention, in n blocks BLK1, ..., BLKi, ..., BLKn, n being a number natural integer strictly greater than 1, all BLKi blocks advantageously having a similar size, preferably of the order of RAM memory space reserved for the write buffer effect and called buffer.

For example, a 2 kByte computer program can be divided into eight BLK1, ..., BLK8 blocks of approximately 256 Bytes each.

The card can be in a loading state, i.e. in a state as it waits for the PRG program to be loaded or no.

When the card is in the loading state, an area FLG memory thereof, located in EEPROM memory, is written by data, for example binary, indicative of said state of loading FLG = Y. Otherwise, FLG = N.

When the card enters the useful electromagnetic field of communication of an emitting device EM1, a dialogue without contact is established between said card and said emitting device EM1, dialog during which the loading status of the card is checked or even changed if a loading decision is made while the card was initially in the state of not loading FLG = N.

In case FLG = Y and if the PRG program is loaded has not started, information I (n), indicative of the number n of blocks BLKi which the card must receive is transmitted by the emitter EM1 to said card.

This indication I (n) is received by the card, in particular with the BLK1 block, the set I (n) and BLK1 being first recorded in the card's buffer memory then taken over by the central unit which records the indication I (n), or an indication I '(n) derived from this indication I (n), in a COUNT memory zone serving as a counter. Likewise, block BLK1 is saved in non-volatile memory EEPROM, at a determined address, for example ADD1. When this BLK1 block is saved at this address ADD1, the memory of COUNT count is decremented COUNT = n-1, meaning that it remains n-1 blocks to load.

If the dialogue between the emitting device EM1 and the card is not not interrupted block BLK2 is received, stored in buffer memory, then in EEPROM at the address ADD2, in particular following ADD1 and the COUNT counter is then decremented again COUNT = n-2. The same is true for each of the BLKi blocks up to BLKn.

However, in the case where the dialogue between the sending device EM1 and the card is interrupted, for example, in case the card leaves the useful electromagnetic field of the EM1 transmitter, the BLKi block loading is interrupted, the card being always in the loading state FLG = Y.

It is then necessary that the card enters the field of a new EMj transmitter also having a copy of the program PRG divided into BLK1, ..., BLKi, ..., BLKn blocks for loading resume, or the card re-enters the field the EM1 transmitter. This new transmitter EMj may be the transmitter EM1.

EMj then questions the card asking if it is in a state loading. She replies that this is indeed the case, had with regard to the presence of the indication FLG = Y.

EMj then interrogates the card on the number of blocks loaded. This responds that i-1 blocks have been loaded, taking into account that COUNT = i-1.

Charging then resumes, with this new EMj transmitter, at BLKi block and continues to BLKn block, unless a new interruption makes it necessary to pass the card through the field of a new transmitter EMj.

When the BLKn block is loaded, the counter is at zero COUNT = 0 then the card is put in the state of non-loading FLG = N.

So regardless of the length of the PRG program to load, BLKi block loading coupled with counting of loaded blocks allows, in particular in the case of contactless cards, to loading an entire program without the dialogue interruptions between the card and the transmitting devices require reloading the program from the start.

Claims (3)

1. Method for loading computer programs into a memory of a portable memory object having a contactless operating mode, particularly a chip card, from one or more transmitting devices EMA, ..., EMj, ... EMp, p being a whole number, characterized in that it includes the following steps in which:

   the computer program is divided into n blocks BLK1, ... BLKi, ..., BLKn, n being a whole number greater than 1;

   a piece of information I(n) indicating the number n of blocks to be loaded is transmitted to the portable object;

   the blocks BLK1, ..., BLKi, ...., BLKn are loaded without contact into a memory of the portable object;

   the loading of the blocks BLK1, ..., BLK2, ..., BLKn is interrupted during the loading of a block BLKi;

   the loading of the blocks is resumed from block BLKi; and

   each block BLKi loaded is counted in the portable object.
2. Method according to any of the preceding claims, characterized in that it also comprises a step in which:

   means FLG of the portable object indicate to a transmitting device EMj the loading state FLG = Y or nonloading state FLG = N of the portable object.
3. Method according to claims 1 or 2, characterized in that it also comprises the following step in which:

   prior to the resumption of the loading of the block BLKi, the loading or nonloading state of the portable object is verified.